Benjamin f



(No Model.)

I B. P. STEPHENS. Tape'r" Ja w for Vises.

Patented Nov. 30,1880.

N PETERS,PHQTOUTNOCJ(APHER, WASHINGTON, D, C.

UNITED STATES PATENT FFHIE.

BENJAMIN F. STEPHENS, OF BROOKLYN, YORK.

TAPER JAW FOR VISES.

SPECIFICATION forming part of Letters Patent No. 234,930, dated November30, 1880,

Application filed April 6, 1880.

To all whom it may concern Be it known that I, BENJAMIN F. STEPHENS, ofBrooklyn, in the county of Kings and State of New York, have invented anImprovement in Taper Jaws for Vises, of which the following is aspecification.

In Letters Patent granted April 9, 1872, to A. P. Stephens, No. 125,625,a taper -jaw attachment is shown in which the backof the jaw is asegment ofa circle, and saidjaw slides endwise in a similarly shapedjaw-block. Difiiculty arises in making these, because the segmental jawis of steel and does not retain its shape perfectly after it has beenfitted and then tempered; hence there is considerable eX pense ingrinding the same or otherwise fitting it into the jaw-block before orafter hardening, and if the parts do notfit with great accuracy thefriction prevents the proper freedom of movement.

My present invention is an improvement upon the aforesaid invention,whereby I am enabled to fit the segmentaljaw into thejawblock with muchless expense than heretofore, and thejaw is less liable to bind thanheretofore. It is to be borne in mind that in clamping a wedgeshapedarticle the jaw has to slide endwise with but very little friction;otherwise the jaw will not accommodate itself to the surface of thetapering article; hence the parts must be so made that there is nothingthat can cause one surface to bind against the other.

I make use of separate bearing-studs secured within the jaw-block forthe segmental jaw to slide against. Said studs are adapted to beingtitted and hardened, if desired, and they are the only portions againstwhich the segmental jaw bears, and hence thejaw-block can be of castmetal and require but little finishin g, and the parts do not becomeobstructed by fine particles of metal that may pass in between thejawand jaw-block.

In the drawings, Figure l is a plan of the taper jaw. Fig. 2 is aVertical section at the line at w, and Fig. 3 is a-plan of the jaw-blockwith the segmental jaw removed. Fig. 4 is a plan; and Fig. 5 is asection at the line y y of the taper jaw, showing the jaw-block madewith a level flange or rest for the vise-jaw.

The jaw-block a is made of a proper size and shape. It may be one sideor jaw of a vise, or

(No model.)

it may be a block to be attached to or placed upon a vise-jaw.

b is the segmental jaw, the back being an arc of a circle and the face aplane, similar to that in aforesaid patent.

The lower part of the block a is made with a flange, 0, upon which reststhe jaw b, and it is preferable to provide ribs upon the surface of thisflange c, as shown at c, Fig. 3, so that the surfaces of these ribs maybe filed off to form a proper bearing for thejaw.

There is, by preference, a slot, i, in this flange c, for the bolt orscrew it, that attaches this jaw 12, said slot being an arc of a circlehaving the same center as the back of the jaw.

The bearing-studs 0 are preferably of steel. They are introduced intorecesses in the jawblock a. I find it preferable to use round studsintroduced into holes bored into thejawblock, the-studs projectingbeyond the curved face of the jaw-block, and being tiled otf more orless to form a flat or nearly flat bearing for the curved side of thesegmental jaw. This jaw may be of cast or wrought iron, with a steelface either welded or otherwise secured to the iron. This lessens thecost of construction, and thejaw is not warped in tempering.

These bearing-studs may be inserted at an inclination, if desired,instead of being parallel to the curved face of the segmental jaw; but Iprefer to make them in the manner shown, and to secure them in place bysmall screws or pins inserted from below the flange c; or the lower endsof the bearing-studs may be reduced in size to form pins that passthrough the lower part ofthe jawblock and are riveted up.

The surface of the segmental jaw may be concave to receive aface-piece,p, the back of which is a cylindrical segment of correspondingcurvature, the parts being attached by a screw passing through avertical slot in the face-piecep into thejaw I), as shown by dottedlines. This allows the jaw to accommodate itself to any irregular taperof the article that is being held, as indicated by dotted lines in Fig.2.

I have shown horizontal bearing-studs t in the curved face of the jaw11, against which the convex back of the face-piece p rests.

In Fig. 2 the flange 0 is represented at a IOU slight backwardinclination. The same, however, might be made level, as shown in Fig. 5,and the face of thejaw may he plain without the auxiliary face 19, asshown in Figs. 4 and 5.

I claim as my invention- 1. The combination, with the segmental visejawand jaw-block, of hearing-studs inserted into recesses in the jaw-block,and against which hearing-studs the curved back of the segmental jawrests, substantially as set forth.

2. The t'ace-piecep, having a curved back, in combination with thesegmental vise-jaw, having a curved face, and hearing studs 15 to re-BENJ. F. STEPHENS.

Witnesses G130. T. PINOKNEY, Orms. H. SMITH.

